CN102719585A - Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity - Google Patents
Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity Download PDFInfo
- Publication number
- CN102719585A CN102719585A CN2012102191625A CN201210219162A CN102719585A CN 102719585 A CN102719585 A CN 102719585A CN 2012102191625 A CN2012102191625 A CN 2012102191625A CN 201210219162 A CN201210219162 A CN 201210219162A CN 102719585 A CN102719585 A CN 102719585A
- Authority
- CN
- China
- Prior art keywords
- rotary hearth
- hearth furnace
- gas
- flue gas
- oxygen
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Manufacture Of Iron (AREA)
- Waste-Gas Treatment And Other Accessory Devices For Furnaces (AREA)
Abstract
The invention belongs to the technical field of rotary hearth furnaces, and in particular relates to a method for improving heat efficiency of a rotary hearth furnace and lowering smoke quantity. The method is characterized in that during the operation process of the rotary hearth furnace, oxygen with volume purity greater than or equal to 85% is used as a combustion-supporting medium. The method can effectively improve the heat efficiency of the rotary hearth furnace and obviously lower the smoke quantity of the rotary heart furnace, and the smoke can be used for preparing dry ice or can be used for soft drink factories.
Description
Technical field
The invention belongs to the rotary hearth furnace technical field, be specifically related to a kind of rotary hearth furnace thermo-efficiency and method that reduces exhaust gas volumn of improving.
Background technology
In recent years, advantage such as rotary hearth furnace is strong with its adaptability to raw material, and operating procedure is flexible has obtained development fast at home and abroad.Rotary hearth furnace can not only be handled the straight carbon steel dust; Aspect handling the stainless steel dust, can not only remove harmful elements such as lead in the dust, zinc, and the sponge iron that obtains (DRI), compare with steel scrap; Residual element Cu, Co, Cr content are low, are the high quality raw material that Electric furnace steel making is produced high-quality molten steel.Rotary hearth furnace also can be used for handling iron ore, because this technology need not the preparation of fuel and the deep processing of raw material, can also handle Iron And Steel Plant and give up admittedly, helps Iron And Steel Plant's energy-conserving and environment-protective and Sustainable development, thereby extremely metallurgical expert of boundary and scholar's concern.
The rotary hearth furnace working temperature is generally 1200 ℃-1400 ℃, and available fuel comprises Sweet natural gas, reacted gas, coke-oven gas, coal gas of converter and gas maked coal, adopts air-breathing usually.Flue-gas temperature is about 1050 ℃, because exhaust gas volumn is big, flue-gas temperature is high, and flue gas is taken away 50% of rotary hearth furnace heat income approximately, causes rotary hearth furnace thermo-efficiency low, becomes restriction rotary hearth furnace development key factor.Owing to adopt air-breathing, about 70% is N in the smoke components in addition
2, N
2Be monoatomic gas, radiation capacity is very low, when carrying out flue gas waste heat recovery, does not have practical significance basically, and therefore economic recovery rotary hearth furnace flue gas overwhelming majority waste heat is difficulty comparatively.
Summary of the invention
Problem to be solved by this invention is to prior art; A kind of rotary hearth furnace thermo-efficiency and method that reduces exhaust gas volumn of improving proposed; This method can effectively improve rotary hearth furnace thermo-efficiency and significantly reduce the rotary hearth furnace exhaust gas volumn, and flue gas can be used for producing dry ice or steam supply water factory uses.
The technical scheme that the present invention solves the problems of the technologies described above employing is: a kind of rotary hearth furnace thermo-efficiency and method that reduces exhaust gas volumn of improving, it is characterized in that: in the rotary hearth furnace working process, combustion-supporting medium adopts the oxygen of bulk purity >=85%.
In the said rotary hearth furnace working process; The flue gas that the rotary hearth furnace burning produces is sent into smoke gas afterheat heat exchanger preheated oxygen and combustion gas after residual heat boiler for exchanging heat; The flue gas that rotary hearth furnace produces gets into waste heat boiler; The steam that waste heat boiler produces is sent to plant generator, gets into smoke gas afterheat heat exchanger through the flue gas behind the waste heat boiler, after the hot flue gas after the smoke gas afterheat heat exchanger heat exchange is through dedusting, be used to produce dry ice or further behind the Cress steam supply water factory use.
Principle of the present invention is: rotary hearth furnace adopts full-oxygen combustion, compares with air-breathing, and reach identical temperature and fuel consumption in the stove and reduce 60-70%, the 30-35% when exhaust gas volumn is air-breathing, the flue gas staple of generation is CO
2And H
2O, both are the polyatomic molecule with high radiation coefficient, are beneficial to furnace heat transfer, are beneficial to simultaneously through radiative transfer and reclaim and utilize fume afterheat.Because smoke components is mainly CO
2And water vapour, can produce dry ice or steam supply water factory and use, realize refuse reclamation.
The invention has the beneficial effects as follows: combustion-supporting medium adopts the oxygen of bulk purity >=85%, has the following advantages:
(1) exhaust gas volumn is little, and NOx content subtracts (said X is 1,2) greatly in the flue gas, and exhaust gas volumn is about the 30-35% when adopting air-breathing;
Exhaust gas volumn was few when (2) total oxygen was combustion-supporting, took away less calories, and rotary hearth furnace thermo-efficiency significantly improves.The rotary hearth furnace flue-gas temperature is about 1050 ℃, and when adopting air-breathing, because exhaust gas volumn, the heat of high-temperature flue gas band rotary hearth furnace about 50% causes rotary hearth furnace heat to imitate lower.When adopting comburant oxygen, since the exhaust gas volumn minimizing, the less calories of taking away, and rotary hearth furnace thermo-efficiency significantly improves; Rotary hearth furnace thermo-efficiency of the present invention is 64-74%;
(3) smoke components is mainly CO during full-oxygen combustion
2And H
2O, the blackness of flue gas is much bigger during than air-breathing, and flame transmission speed W during full-oxygen combustion
O2Fast (the experimental formula: Wa=W of velocity of propagation Wa during than air-breathing
O2(1-0.01N
2-0.01CO
2), N in the formula
2And CO
2Be respectively N in the flue gas
2And CO
2Percentage composition), therefore the heat transfer capacity to furnace charge increases, rotary hearth furnace productivity can improve 10-20%;
(4) flue gas waste heat recovery efficient is high during full-oxygen combustion.Smoke components is mainly CO during full-oxygen combustion
2And H
2O, both are polyatomic molecule, and blackness is high, helps radiative transfer, improves flue gas waste heat recovery efficient;
(5) full-oxygen combustion helps reducing fuel consumption.Compare with air-breathing, reach identical temperature and fuel consumption in the full-oxygen combustion stove and reduce 60-70%, be of value to and save production cost;
(6) because smoke components is mainly CO
2And water vapour, can produce dry ice or steam supply water factory and use, realize refuse reclamation;
(7) full-oxygen combustion rotary hearth furnace greenhouse gas emissions significantly reduce, energy-saving and emission-reduction, environmental friendliness.
Description of drawings
Fig. 1 is the technological process of production figure of rotary hearth furnace of the present invention.
Embodiment
Through Fig. 1 production stage of the present invention is done further explanation below; But be not construed as limiting the invention: oxygen (bulk purity >=85%; Be the oxygen source among Fig. 1) and combustion gas (comprising any one or multiple mixing in Sweet natural gas, reacted gas, coke-oven gas, coal gas of converter or the gas maked coal) by any proportioning respectively behind smoke gas afterheat heat exchanger; Send into the rotary hearth furnace internal combustion by the required reacting weight of burning heat is provided; The flue gas that the rotary hearth furnace burning produces is sent into smoke gas afterheat heat exchanger preheated oxygen and combustion gas after residual heat boiler for exchanging heat; The flue gas that rotary hearth furnace produces gets into waste heat boiler; The steam that waste heat boiler produces is sent to plant generator, gets into smoke gas afterheat heat exchanger (being the interchanger among Fig. 1) through the flue gas behind the waste heat boiler, the hot flue gas after the interchanger heat exchange can be used for producing after through dedusting dry ice (being the dry ice manufacturing among Fig. 1) or further behind the Cress steam supply water factory use.
Embodiment 1
Present embodiment acts as a fuel with coke-oven gas, and the coke-oven gas composition is as shown in table 1, with the comburant oxygen of bulk purity 90%.Rotary hearth furnace year is handled 100,000 tons in Iron And Steel Plant's straight carbon steel dust; The dust composition is as shown in table 2, and temperature is controlled to be 1300-1350 ℃ in the stove, and the pelletizing tapping temperature is 1000 ℃; Flue-gas temperature is 1050 ℃; Flue gas goes out the waste heat boiler temperature and is controlled to be 300 ℃, and oxygen preheat is 200 ℃, and gas-preheating is 150 ℃.Flue gas can be used for producing dry ice or steam supply water factory uses.
Above-mentioned Production Flow Chart oxygen depletion amount is 3800Nm3/h, and the coke-oven gas flow is 1380Nm
3Temperature is 1366 ℃ in the/h, stove, and the flue-gas temperature of coming out of the stove is 1046 ℃, and flue gas flow is 5900Nm
3/ h produces about 80,000 tons/year of sponge iron, produces quantity of steam 2.4t/h, and generated energy 83KW/h, rotary hearth furnace thermo-efficiency are 67%.If adopt air-breathing, the coke-oven gas consumption is 3800Nm to the same terms down
3/ h, exhaust gas volumn is 32597Nm
3/ h, the thermo-efficiency of rotary hearth furnace is about 30%.
Table 1 coke-oven gas composition (volume %)
| CO 2 | H 2S | O 2 | CmHn | CO | H 2 | CH 4 | N 2 |
| 2 | 0 | 0.7 | 2.3 | 10 | 55 | 20 | 10 |
Table 2 straight carbon steel dust composition (quality %)
| FeO | Fe 2O 3 | ZnO | SiO 2 | MgO | CaO | Al 2O 3 | S | Other |
| 19.25 | 46.85 | 0.07 | 3 | 0.84 | 5.95 | 1.35 | 0.20 | 22.49 |
Embodiment 2
Present embodiment acts as a fuel with the gas mixture of coke-oven gas and coal gas of converter, and the mixed gas composition is as shown in table 3, with the comburant oxygen of bulk purity 95%.Rotary hearth furnace year is handled 50,000 tons in Iron And Steel Plant's stainless steel dust, and the dust composition is as shown in table 4, and temperature is controlled to be 1250-1350 ℃ in the stove; The pelletizing tapping temperature is 1000 ℃, and flue-gas temperature is 1050 ℃, and flue gas goes out the waste heat boiler temperature and is controlled to be 300 ℃; Oxygen preheat is 200 ℃, and gas-preheating is 150 ℃.Flue gas can be used for producing dry ice or steam supply water factory uses.
Above-mentioned Production Flow Chart oxygen depletion amount is 2067Nm
3/ h, gas flow is 910Nm
3Temperature is 1301 ℃ in the/h, stove, and the flue-gas temperature of coming out of the stove is 1051 ℃, and flue gas flow is 2927Nm
3/ h produces about 40,000 tons/year of sponge iron, produces quantity of steam 1.21t/h, and generated energy 41.8KW/h, rotary hearth furnace thermo-efficiency are 64%.If adopt air-breathing, combustion gas gas consumption is 2600Nm to the same terms down
3/ h, exhaust gas volumn is 15872Nm
3/ h, the thermo-efficiency of rotary hearth furnace is about 28%.
Table 3 gas component (volume %)
| CO 2 | H 2S | O 2 | CmHn | CO | H 2 | CH 4 | N 2 |
| 10 | 0 | 1.35 | 1.15 | 35.0 | 28.0 | 12 | 12.5 |
Table 4 stainless steel dust composition (quality %)
| FeO | Fe 2O 3 | NiO | Cr 2O 3 | ZnO | ?SiO 2 | MgO | CaO | Al 2O 3 | S | Other |
| 24.75 | 30.37 | 1.42 | 5.1 | 0.04 | 3.8 | 0.69 | 9.50 | 0.86 | 0.12 | 23.35 |
Embodiment 3
Present embodiment acts as a fuel with Sweet natural gas, and gas component is as shown in table 5, with the comburant oxygen of bulk purity 98%.Rotary hearth furnace year is handled 200,000 tons of iron ore concentrates, and composition of ores is as shown in table 6, and temperature is controlled to be 1300-1350 ℃ in the stove; The pelletizing tapping temperature is 1000 ℃, and flue-gas temperature is 1050 ℃, and flue gas goes out the waste heat boiler temperature and is controlled to be 700 ℃; Oxygen preheat is 500 ℃, and gas-preheating is 150 ℃.Flue gas can be used for producing dry ice or steam supply water factory uses.
Above-mentioned Production Flow Chart oxygen depletion amount is 6141Nm
3/ h, gas discharge are 1130Nm
3Temperature is 1354 ℃ in the/h, stove, and the flue-gas temperature of coming out of the stove is 1051 ℃, and flue gas flow is 11983Nm
3/ h produces about 160,000 tons/year of sponge iron, produces quantity of steam 5t/h, and generated energy 171KW/h, rotary hearth furnace thermo-efficiency are 74%.If adopt air-breathing, Sweet natural gas gas consumption is 3950Nm to the same terms down
3/ h, exhaust gas volumn is 72379Nm
3/ h, the thermo-efficiency of rotary hearth furnace is about 27%.
Table 5 gas component (volume %)
| CmHn | CH 4 | N 2 |
| 1 | 98 | 1 |
Table 6 iron ore concentrate composition (quality %)
| FeO | Fe 2O 3 | ZnO | ?SiO 2 | MgO | CaO | Al 2O 3 | S | Other |
| 28.5 | 64 | 0 | 6.13 | 0.27 | 0.35 | 0.56 | 0.04 | 0.15 |
Claims (2)
1. one kind is improved rotary hearth furnace thermo-efficiency and the method that reduces exhaust gas volumn, it is characterized in that: in the rotary hearth furnace working process, combustion-supporting medium adopts the oxygen of bulk purity >=85%.
2. a kind of rotary hearth furnace thermo-efficiency and method that reduces exhaust gas volumn of improving according to claim 1; It is characterized in that: in the said rotary hearth furnace working process; The flue gas that the rotary hearth furnace burning produces is sent into smoke gas afterheat heat exchanger preheated oxygen and combustion gas after residual heat boiler for exchanging heat; The flue gas that rotary hearth furnace produces gets into waste heat boiler; The steam that waste heat boiler produces is sent to plant generator, gets into smoke gas afterheat heat exchanger through the flue gas behind the waste heat boiler, after the hot flue gas after the smoke gas afterheat heat exchanger heat exchange is through dedusting, be used to produce dry ice or further behind the Cress steam supply water factory use.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102191625A CN102719585A (en) | 2012-06-29 | 2012-06-29 | Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2012102191625A CN102719585A (en) | 2012-06-29 | 2012-06-29 | Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN102719585A true CN102719585A (en) | 2012-10-10 |
Family
ID=46945450
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN2012102191625A Pending CN102719585A (en) | 2012-06-29 | 2012-06-29 | Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102719585A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104861991A (en) * | 2015-04-23 | 2015-08-26 | 武汉钢铁(集团)公司 | Coke oven flue gas recycling system and processing method |
| CN107840337A (en) * | 2017-11-08 | 2018-03-27 | 中冶华天南京工程技术有限公司 | A kind of system and method that dry ice is prepared using blast furnace gas and liquid oxygen |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1186863A (en) * | 1997-11-27 | 1998-07-08 | 北京兰斯节能技术开发中心 | Bead iron producing process in rotary hearth furnace and its separating method |
| CN1201882A (en) * | 1997-06-09 | 1998-12-16 | 中国科学院大连化学物理研究所 | Combustion method for industrial heating furnace by membrane local rich oxygen supply |
| CN1270232A (en) * | 1999-04-14 | 2000-10-18 | 北京兰斯节能技术开发中心 | Technology for smelting iorn in blast furnace with pre-reducing coal-base pellets |
| JP2007147261A (en) * | 2005-10-31 | 2007-06-14 | Kobe Steel Ltd | Rotary hearth furnace and method of operating the same |
| CN101445869A (en) * | 2008-12-22 | 2009-06-03 | 莱芜钢铁集团有限公司 | Method for manufacturing metallic pellets by direct reduction of oxygen-enriched combustion in rotary furnace |
| US20100052226A1 (en) * | 2008-08-29 | 2010-03-04 | Global Research and Engineering, LLC | Rotary hearth furnace for treating metal oxide materials |
-
2012
- 2012-06-29 CN CN2012102191625A patent/CN102719585A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1201882A (en) * | 1997-06-09 | 1998-12-16 | 中国科学院大连化学物理研究所 | Combustion method for industrial heating furnace by membrane local rich oxygen supply |
| CN1186863A (en) * | 1997-11-27 | 1998-07-08 | 北京兰斯节能技术开发中心 | Bead iron producing process in rotary hearth furnace and its separating method |
| CN1270232A (en) * | 1999-04-14 | 2000-10-18 | 北京兰斯节能技术开发中心 | Technology for smelting iorn in blast furnace with pre-reducing coal-base pellets |
| JP2007147261A (en) * | 2005-10-31 | 2007-06-14 | Kobe Steel Ltd | Rotary hearth furnace and method of operating the same |
| US20100052226A1 (en) * | 2008-08-29 | 2010-03-04 | Global Research and Engineering, LLC | Rotary hearth furnace for treating metal oxide materials |
| CN101445869A (en) * | 2008-12-22 | 2009-06-03 | 莱芜钢铁集团有限公司 | Method for manufacturing metallic pellets by direct reduction of oxygen-enriched combustion in rotary furnace |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104861991A (en) * | 2015-04-23 | 2015-08-26 | 武汉钢铁(集团)公司 | Coke oven flue gas recycling system and processing method |
| CN107840337A (en) * | 2017-11-08 | 2018-03-27 | 中冶华天南京工程技术有限公司 | A kind of system and method that dry ice is prepared using blast furnace gas and liquid oxygen |
| CN107840337B (en) * | 2017-11-08 | 2019-10-22 | 中冶西北工程技术有限公司 | A kind of system and method preparing dry ice using blast furnace gas and liquid oxygen |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101538632B (en) | Preparation process and device of sponge iron | |
| CN101538630B (en) | Process and device for preparing chromium iron by using chromium ore powder | |
| CN101575654B (en) | Process and device for preparing iron alloy containing nickel and nickel-chromium | |
| CN102010924B (en) | Method for producing directly reduced iron from coal | |
| CN104831056B (en) | A kind of preheating of fine chrome mine pelletizing and method of roasting | |
| CN101724726B (en) | Method and device for ironmaking by smelting | |
| CN112813219B (en) | System and process for realizing near zero emission by directly reducing iron by ammonia gas | |
| CN101445869A (en) | Method for manufacturing metallic pellets by direct reduction of oxygen-enriched combustion in rotary furnace | |
| CN110093504B (en) | Method and system for preparing titanium-rich material by using high-calcium-magnesium titanium concentrate | |
| CN102874850A (en) | Roasting system and roasting method for lithium-ore acidification by using externally-heated type rotary furnace | |
| CN101956037A (en) | Method and device for indirect heating type reduction iron making | |
| CN104313228B (en) | One utilizes CH4on-catalytic is oxygen-enriched converts the direct-reduction technique producing sponge iron | |
| CN102001837A (en) | Method and device for calcining materials by using low calorific value fuel | |
| CN112744792A (en) | Method for preparing metal oxide powder and nitric acid by decomposing nitrate | |
| CN204803378U (en) | Rotary hearth furnace | |
| CN106521054B (en) | Blast furnace slag waste heat recycles and flue gas CO2Adsorption desorption coupled system and method | |
| CN105314894A (en) | Rotary kiln device and method for indirectly producing lime and recycling carbon dioxide | |
| CN102605132A (en) | Method for producing direct reduction iron by aid of coke oven gas | |
| CN106244758A (en) | A kind of system and method efficiently utilizing body of heater fume afterheat to process iron-containing resource | |
| CN102719585A (en) | Method for improving heat efficiency of rotary hearth furnace and lowering smoke quantity | |
| CN107815516A (en) | A kind of external-heat coal base upright furnace for being used to produce DRI | |
| CN115820954A (en) | Blast furnace blowing CO 2 Biomass charcoal tempering co-production carbon emission reduction system and application process | |
| CN207738789U (en) | A kind of external-heat coal base upright furnace for producing direct reduced iron | |
| CN204625480U (en) | A kind of rotary kiln device of constant temperature indirect calcination Wingdale | |
| CN204625479U (en) | A kind of indirect calcination is produced lime, is reclaimed the rotary kiln device of carbonic acid gas |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C02 | Deemed withdrawal of patent application after publication (patent law 2001) | ||
| WD01 | Invention patent application deemed withdrawn after publication |
Application publication date: 20121010 |